Product Description:

The PSI63C0.735-L1 is a medium-frequency inverter produced by Bosch Rexroth Indramat within the PSI Frequency Inverters series. Designed for resistance welding and other high-current automation tasks, the unit converts three-phase factory power into a controlled medium-frequency output, allowing the controller to regulate heat and weld penetration with millisecond precision. Its medium-frequency architecture reduces the need for bulky line-frequency transformers while providing the rapid control response needed to maintain consistent weld quality.

The power section accepts a mains input range of 400–480 VAC at either 50 or 60 Hz and draws up to 110 A under nominal load. Internally, the bridge switches at 1000 Hz, while a closed-loop regulation cycle of 1 ms aligns the current with programmed weld profiles. A TriCore CPU coordinates inverter timing, and an integrated supply provides 24 VDC at 2 A for sensors and I/O devices. The stop circuit can sink 3 A at the same voltage. Air cooling removes 69 W under basic cabinet conditions, with cabinet heat dissipation rising to 170 W at full output, while dedicated inverter components dissipate up to 360 W. The minimum conductor cross-section is 35 mm², and the terminal clamps accept cables up to 50 mm² to carry high primary currents. Three programmable weld times are stored in nonvolatile memory, and the Ethernet timer interface supports rapid communication with the production line.

Operating conditions conform to climatic category 3K3 according to EN 60721-3-3. The permitted operating temperature ranges from +10 to +55 °C, while storage is allowed from -25 to +70 °C. The inverter has an IP20 protection rating, weighs approximately 20 kg, and mounts inside an air-circulated switch cabinet. Connected welding transformers can draw up to 800 A on the primary side, while the secondary surge capacity reaches 36 kA with a PSG 3100 transformer for short welding pulses. Programmable watchdogs monitor control activity and help detect timing or communication faults during automated welding cycles.